Tampa Mayor Jane Castor is urging residents to heed evacuation orders in the face of the impending threat of Hurricane Milton, which the National Weather Service (NWS) warns could be the most severe hurricane to hit the Tampa area in over a century. The city’s low-lying terrain makes it particularly susceptible to hurricane damage.

“Everyone in the Tampa Bay region needs to be aware of what’s happening with Hurricane Milton and you need to follow the evacuation orders,” Castor told CBS News. “If Milton stays on the designated path, it will be catastrophic.” 

The Tampa Mayor’s Office did not immediately respond to TIME’s request for comment. 

While the city has weathered other tropical storms in the past, Hurricane Milton, a Category 5 storm poised to make landfall in Florida on Wednesday, is cause for concern because Tampa is vulnerable to storm surges due to its shallow waters. Milton’s storm surge is predicted to raise water levels by eight to 12 feet in Tampa Bay, particularly if the peak surge coincides with high tide.

“The deepest water will occur along the immediate coast near and to the south of the landfall location, where the surge will be accompanied by large and dangerous waves,” the NWS said in its warning.

Tampa, like many other coastal communities, has experienced rising sea levels due to climate change in recent years. The 2010 Statewide Regional Evacuation Study for Tampa Bay found that 2 million people reside within what would be considered an evacuation zone if a Category 5 hurricane impacted the Tampa region, a study which underscored the seriousness of the threat. That same study found that a hurricane of Milton’s magnitude would result in an estimated 2,000 deaths and cause $250 billion in damages to the city.  

The storm arrives as Florida recovers from the impact of Hurricane Helene, and residents are still awaiting debris collection. Gov. Ron DeSantis declared a state of emergency on Saturday afternoon, and mandatory evacuation orders are in place for four counties, including Hillsborough County, where Tampa is located. 

As of Monday afternoon, Hurricane Milton was positioned approximately 100 miles southwest of Tampa. With winds measuring 175 mph that will have a Level 4 wind threat impact on the greater Tampa Bay area, according to the NWS, the storm could lead to wall and roof failures in buildings, the destruction of mobile homes, power outages, and fallen trees. 

The last hurricane to directly impact Tampa Bay was the Tarpon Springs Hurricane of 1921. As a Category 3 storm, it caused significant damage (worth nearly $180 million today when adjusted for inflation).

Hurricane Milton will bring flooding that is expected to affect both primary and secondary roads, parking lots, buildings, and homes. Rescues may also be necessary, particularly in low-lying areas.

The NWS is strongly urging Tampa Bay residents to evacuate if instructed to do so, and to complete all hurricane preparations by Tuesday night. Tolls are being waived for the next week to expedite travel flow as people evacuate.

The Florida Department of Transportation is providing updates on local traffic, road blockages, and closures on their website.